Automatic joint breaker



Jan. 5, 1932. P. F. MURRAY AUTOMATIC JOINT BREAKER Filed April 21, 1930 Patented Jan. 5, 1932 UNITED STATES IPEXTON F. MURRAY, OF MONTEBELLO, CALIFORNIA AUTOMATIC JOINT BREAKER Application filed April 21,

My invention relates to an automatic joint breaker of the particular type disclosed in my co-pending ag plication for patent filed May th, 1929, erial No. 363,308.

6 The principal objects of my present invention are, to generally improve upon and simplify the construction of the joint breaker disclosed in my aforesaid co-pendin patent application, as well as other similar orms of joint breakers or catheads and further, to provide a -oint breaker'that may be conveniently utilized with practically all standard forms of rotary well drilling rigs and to construct the joint breaker so that it will permit the tongs with which it is associated to be applied to the tubes or pipes in any position, thereby greatly facilitating the work 1nc1- dent to the breaking of pipe joints and the like.

Further objects of my invention are, to provide a relatively simple, practical and inexpensive cathead or joint breaker that is entirely automatic in its releasing action and further, to provide a joint breaker that is stron and substantial in structure and which may be conveniently thrown into operation so as to exert a pull or jerk upon the line that is connected to the pipe tongs.

With the foregoing and other objects in View, my invention consists in certain novel features of construction and arrangement of parts that will hereinafter be more fully described and claimed and illustrated in the accompanying drawings,'in which:

Fig. 1 is an elevational view of a cathcad or joint breaker constructed in accordance with my invention and with parts thereof broken away and in section;

Fig. 2 isan elevational view looking in the direction indicated by the arrow 2 in Fig. 1 and showing a portion of the curved rail broken away.

Referring by numerals to the accompanyr ing drawings which illustrate a practical embodiment of my invention, 10 designates one of the jack posts of a rotary welldrilling rig and secured to said jack post is a bearing 11 in which is j ournaled a constantly rotating shaft 12 and secured upon the end of the latter is a spool or drum 13, upon which is adapted centric with the axis of shaft 12.

1930. Serial N0. 445,878.

to wind, a chain or cable that may be used in drilling operations or for the operation of parts of the drilling rig.

Formed integral with or fixed to the inner portion of the spool or drum 13 is a sheave 14, provided in its periphery with a channel 15, and formed on the peri hery of said sheave within said channel is alug or shoulder Secured in any suitable manner to the outer face of the jack post 10 are the end portions 17 of a substantially semi-circular rail 18 that lies immediately adjacent to the periphery of the sheave 14 and said rail is con- Formed in the outer face of the rail 18 is a groove or channel 19 that is approximately half round in cross section.

Arranged to slide freely upon the semicircular rail 18 is a block or runner 20, to the underside of which is connected one end of the cable 21, that is utilized in the operation of the pipe, tongs or other parts of the drilling paraphernalia that may be advantageously actuated by pulling strains of a cable, chain or the like.

Formed integral'with or fixed to the lower end of rail 18 is a block 22, through the lower portion of which is formed an openin for the accommodation of the cable 21 and ournaled in the lower ortion-of this block is v a roller 23 that functions as a rolling support for the cable as it passes onto and from the cathead.

Block 22 is provided with a flat front face '24 that functions as a stop against which the rear end of the block or runner 20 engages when the same is at the lower end of its travel on rail 18. v

Hinged on the upper front portion of the runner 20 is one end of a pawl or dog 25, the free end of which is adapted to engage against shoulder. 16 on the periphery of shea ve 15 and secured to pins 26 that project outwardly from the sides of the pawl or dog are retractile springs 27, the lower ends of which are connected to pins 28 that project from the sides of runner 20. The spr ngs 27 normally hold the pawl 25 inwardly. against the upper face of the runner 20 so that the v ecured'to the short arm of hell crank 29 is a flexible member 31 such as a cable that extends over suitably located pulleys 32 to a point convenient to the hand of an operatofi Formed integral with the upper end portion of the semi-circular rail 18 and arranged on the inside thereof are concentric fin ers 33 rovided on their forward upperportions wit cam surfaces 34 that are adapted to engage the pins 26 on runner 20 as the latter approaches the upper end of its travel.

Under normal conditions the pull upon the jerk line or cable 21 holds runner 20 on rail 18 immediately'in front of block 22 and the springs 27 retain pawl 25 out of engagement .with the shoulder 16. When it is deslred to impart a pull or jerking movement to the cable, an operator pulls on flexible member 31, thereby swinging bell crank 29 upon its axis and moving the free end of pawl 29 into the path of travel of shoulder 16 on sheave 15.

It will be understood that shaft 12 and the drum and sheave carried thereby are constantly rotating and as a result of the engage:

ment betweenshoulder 16 and awl 25, the latter and the runner 20 to which the pawl is hinged will be caused to travel upwardly on the curved rail 18, thereby imparting a jerk or pullto line 21 and the latter following the runner 20 will pass upwardly through the groove or channel 19 in rail 18.

As the runner approaches the upper end of the semi-circular rail 18, the pins 26 that project from the sides of said runner will engage on the cam surfaces 34 of fingers 33 and such action will pull the free end of the pawl inwardly toward the runner so as to automatically effect a disengagement between said pawl and the shoulder 16 and following such disengagement, the pulling strains resulting from the resistance offered by the tongs or member to which the jerk line '21 is connected, will quickly return the runner and pawl carried thereby to the lower end of the rail.

The downward travel of the runner is limited by the rear face 24 of block 22 and the retractile springs 27 pull the pawl into positiona ainst the upper surface of the runner an the parts occupy such positions until the pawl is again swung outwardly by bell crank 29 that is actuated by the pull cord 31..

Thus it will be seen that I have provided a cathead or joint breaker for rotary oil well drilling rigs that is relatively simple in con struction, mexpensive of manufacture, automatic in its release under ready control of an operator and which joint breaker is very effective in'performing the functions for which it is intended.

It will be understood that minor changes in the size, form and construction of the various parts of my im roved automatic joint breaker may be ma e and substituted for those herein shown and described without departing from the spirit of my invention, 1

.the scope of which is set forth in the apsheave, a runner mounted for sliding movement on said track cooperating means on said sheave and runner for efi'ecting a drlving engagement between the sheave and runner for a portion of a complete revolution of said sheave and a jerk line connected to said run-.

ner.

2. A joint breaker, as set forth in claim 1, means for effecting a driving engagement between the sheave and runner, and means for automatically disengaging the driving connection between said sheave andrunner.

3. In an automatic joint breaker, a sheave mounted for rotation, a shoulder on said sheave, a semi-circular track rail positioned adjacent to and concentric with said sheave, a runnermounted for sliding movement on said track rail, a jerk line connected to said runner anda pawl hinged to said runner and adapted to be engaged by the shoulder on the sheave.

4. A joint breaker, as set forth in claim 3, and with manually operable means for moving said pawl into the path of travel of the shoulder on said sheave. I

5. A joint breaker, as set forth in claim 4, manually operable means for moving said pawl into the path of travel of the shoulder on said sheave and means for automatically disengaging said pawl from said shoulder.

6. In an automatic joint breaker, the combination with a sheave mounted for rotation, of a semi-circular track rail positioned adjacent to and concentric with said sheave, the outer face of which rail is provided with a groove, a runner mounted for sliding movement on said track rail, a jerk line connected the driving engagement between said runner and sheave.

8. In an automatic joint breaker, the combination with a rotary member of a track rail arranged concentric with and partially surrounding said rotary member, a runner mounted for sliding movement upon said with means for automatically breaking the driving engagement between said sheave and runner.

10. A cathead structure comprising a winding sheave having a winding surface for a line, a coupler abutment on said sheave, a line having a coupler for engagement by said abutment whereby to anchor said line to said sheave, a frame partially encompassing said sheave, said frame having a release member to engage said coupler and lift the latter from engagement with said abutment at the end of its travel along said frame, there being an entry end on said frame, a retaining rail on said frame to maintain said coupler in engagement with said abutment during travel of said coupler from the entry end of the frame to said release member, and means to initially place said coupler in engagementwith said abutment.

11. In an automatic joint breaker, a sheave mounted for rotation, a shoulder on said sheave, a substantially semicircular track surrounding said rotary member, a runner mounted for sliding, movement upon said track rail, a jerk line connected to said runner, manually operable means for efi'ecting a driving connection between said runner and sheave, and means for automatically break- I ing the driving engagement between said sheave and runner.

In testimony whereof I aflix my signature.

- PEXTON F. MURRAY. 

